57 Panel "FAKMLC" build

[FAKKY]

Just bought this .....

https://www.amazon.com/Billet-Swivel...5302942&sr=8-7

Hopefully I'll have enough hose to make the 90 degrees on both sides ...... and I'll just use some aluminium 1.5" OD tubing to connect ......


I did find my oil level was a bit high ........ so I drained that ..... and gave constant 12v to the fuel pump with no leaks ...... turned her over .... purred like a kitten. Well a loud kitten.

Wait for this to get delivered ....... will start working on mounting the battery and harness and wiring everything up including gauges and chassis harness .....

[FAKKY]

Looking for ideas on battery groudn to block. OEM had it on passenger side in middle of block by oil pan. Battery will be in default 57 location.
SO want to ground to block .... but cable length is not enough unless I go between headers. Plus heat.

Would back of head be ok - or better to ground to block. I hate spending extra $40 for being a few inches short.

[FAKKY]

went here for now. Not the most "aesthetic" ... but its tied to block.





old AC compressor mounting hole I think

[dsraven]

ground needs to go to engine somewhere AND frame somewhere plus to body somewhere. some will go to engine and a separate one from engine to frame and to body. anywhere on the engine will work. you could go to the engine from battery, then from another place to frame and/or body. a separate ground to the rad support is also a good idea since all the lights up front ground on the rad support. it could be from the frame to the rad support. so battery to engine, engine to frame, frame to rad support. battery to engine, engine to cab, OR, battery to cab as an extra wire from the main battery cable.

[FAKKY]

Originally Posted by dsraven

ground needs to go to engine somewhere AND frame somewhere plus to body somewhere. some will go to engine and a separate one from engine to frame and to body. anywhere on the engine will work. you could go to the engine from battery, then from another place to frame and/or body. a separate ground to the rad support is also a good idea since all the lights up front ground on the rad support. it could be from the frame to the rad support. so battery to engine, engine to frame, frame to rad support. battery to engine, engine to cab, OR, battery to cab as an extra wire from the main battery cable.

thanks

Have battery to block location in pic above.
Have back of head to body via the inner fender holding screws
Have body to frame from same inner fender screw on other side.
I'll place one more from ground of battery to inner fender sheet metal.

[FAKKY]

Floor column support worked out pretty good - really tightended it up. I "might" put sove clear RTV or silicone in the gapes and then wipe down.

[joedoh]

nice solution!

[FAKKY]

Originally Posted by joedoh

nice solution!

Thx Sir. Relatively simple, works wel.. I placed some silcone sealant in the grooves on both sides just to help support the column - but it really doesnt move/flex much now.

Go drivers side inner fenders on ....... starting to look like a truck again.
Need to decide where IM going to stick the ECM. If I could do it over again I would bring it into the CAB probably ...... but not going to cut firewall now. Probably pin it towards front of drivers side inner fender near lights.

[FAKKY]

PCM location ?



Any reason why not ?

[FAKKY]

Trying to understand wiring (AC) generallly but also specific to my setup.
I have a truck GENIII blue/green harness depinned as per LT1swap.
I have the fuse panel from bp automotive here. Has a 2 fans relay, 1 AC relay.

https://www.bp-automotive.com/produc...i-24x-engines/

I bought a coldmaster AC unit (local to me) with a Vintage Air compressor. 2 wire binary Pressure switch on the drier.
I have a puller fan on the radiator
I have a pusher fan on the condensor.

Just going to deal with non PCM controlled to begin with.

Under this scenario I think it would go like this.

Battery +12v => Pin 30 on relay
Drier Pressure switch => Pin 86 on relay (other wire on switch goes to Evap Unit in car). Grounded. 12v+ from ign on other wire.
Ground -> Pin 85 on relay
+12v feed to both AC compressor and condensor fan -> Pin 85

So basically the FAN and the Compressor get power in a NC relay ..... unless the high pressure switch kicks in ... and then the circuit is open and power to fan and compressor is stopped.


Right so far ?
=========================
So here's where it gets a little (more) confusing for me. Due to the BP automotive harness. And main puller fan.
The harness has the following wired to main harness (which was done about 1 year ago).

12v AC compressor (Green) thicker wire
#1 FAN relay dark green (12v for FAN low speed)
#2 FAN relay dark blue (12v for FAN high speed)

Smaller AC request wire (green/white) 12v to engage A/C compressor
Smaller gage AC relay control ground wire (black/white).
Smaller gauge Fan #2 wire (blue)

Instructions on this from BPAUTO say.
1) Ground AC relay control wire.
2) Hook AC request wire to your AC control unit in CAB to power AC.
3) AC compressor wire to compressor.

--- Nothing about FANS. Im guessing thats because the two FAN relays are wired for PCM control ? So better to go that route ?

Trying to understand best way to "merge" the two harnesses so to speak.


** going to post in LSX swap section also.

[joedoh]

Originally Posted by FAKKY

Drier Pressure switch => Pin 86 on relay (other wire on switch goes to Evap Unit in car). Grounded. 12v+ from ign on other wire.
Ground -> Pin 85 on relay
+12v feed to both AC compressor and condensor fan -> Pin 85

I think you mean pin 87 on that last one.


also, think of an automotive style relay as a low current to high current switch. pins 85 and 86 are the low current switch, and pins 87 and 30 are the high current switch. energizing the low current contacts engages the high current ones. so if you only have a low current 12v (-) trigger available and need a high current 12v (+), using a relay set up with your 12v (-) trigger on 85, you would use 12v (+) on 86 (to energize the relay and connect 87 to 30), a high current 12v (+) feed on 87, and the output devices on 30. some people wire a relay backwards, with input on 30 and output on 87, but that is not the way the relay should work, more on that in a second.

so when you say you are using the low pressure switch as one side of the relay, I am a little confused when you talk about grounding the same pin. a low pressure switch is a switch, with two wires, its a normally open switch so that means that the two contacts are open unless there is suitable pressure, and then it is closed, and whatever you have on wire one is what is on wire two. I would set it up grounded because its easier aand safer than as 12v. just ground one wire on the switch, doesnt matter which. the other wire will have ground as long as there is pressure in the line.

so if you wanted to make it work with a low pressure switch (-) interrupt and a 12v (+) switch in the cab, you would wire as

85 (-) from low pressure switch
86 12v (+) from switch on dash
87 FUSED high current 12v (+) (10 ga or better! fused at the battery!)
30 wired to fan and ac clutch.

I would probably use two separate relays for the fan and for the ac clutch because mixing high current (fan) with low current (clutch) can burn up the low current wire with a short, the high current wire fuse wouldnt blow till the smaller one was on fire.

this way, if the low pressure switch opens (low pressure) with the ac turned on in the cab, it wont turn the relay on.

if you have fan triggers in your pcm, you can wire a SECOND relay to that first using

85 (-) pcm trigger
86 12v (+)
87 FUSED high current 12v (+)
30 to 87a on the first relay.

this way, the pcm can turn the fans on for any cooling reason, and when the ac is turned on it holds the fan on if the pcm shuts off.

using 87 as input is the reason this works, the pcm will turn on the fan relay and it will flow from 87a to 30 on the AC relay without energizing the relay. obviously, in this case you will need that second ac relay I talked about so that the pcm doesnt kick on the AC clutch when it turns the cooling fans on.

I can draw all this out, sorry it was long, but i think understanding how it works is better than just pumping out a diagram.

[FAKKY]

Originally Posted by joedoh

I think you mean pin 87 on that last one.

Yes - sorry
Ok ... bare with me ...... thats awesome info .... but my head hurts.
The operation of both harnesses, the PCM, the switch and AC and dual relays .... aargh. lol. ok here I go ....

=======================
If I want the most basic setup for AC.
=======================
Components => Binary switch, compressor, condenser fan.
Compressor and FAN to come on together.

Pin 87 to battery 12v (fused)
Pin 30 split to both compressor and fan
Pin 86 to the back of AC unit in dash (12v signal when turned on).
Pin 85 to wire on binary switch - which is GROUNDED on other wire to chassis.

^^^ this is for AC only.

For radiator/engine coolant FAN in my build ..... since I have the PCM fan .... just have that enabled in PCM for FAN#1 and set temp at say 180 degrees.
Its already protected and enabled via relay and PCM control at that point.

================END OF BASIC/TYPICAL SETUP ==============================


==============================================
If I want the separate relay control 1 for fan and 1 for compressor
Here I can use PCM Fan #2 in BP automotive harness as #1 used for engine fan single speed fan.
======================= =======================

Well ... nope here Im lost ...... I get that your joining two circuits via 87a to have independent control .... based on if the AC is running and PCM signal and pressure switch etc .... but dont get

1) How existing relay is wired in the harness - since I didnt wire it ... Just know it has 12V for fan.

2) Where it gets it ground from

85 (-) pcm trigger
86 12v (+)
87 FUSED high current 12v (+)
30 to 87a on the first relay.

as all of those are 12v signals ?
Unless shared common ground on 1st relay (pin 85 is grounded)

[joedoh]

Originally Posted by FAKKY

1) How existing relay is wired in the harness - since I didnt wire it ... Just know it has 12V for fan.

2) Where it gets it ground from

85 (-) pcm trigger
86 12v (+)
87 FUSED high current 12v (+)
30 to 87a on the first relay.

as all of those are 12v signals ?
Unless shared common ground on 1st relay (pin 85 is grounded)

I am assuming in #2 that the pcm trigger is a ground, (-).

wait. i think I see where you question is coming from. a relay is an electromagnetic switch, it needs power and ground to operate but not in the way something like a 12v clock does. since it is just a low current activated high current switch, pins 85 and 86 are the electromagnet, so it doesnt really matter if you put 12v (+) on 85 or 86, as long as the opposite (in this case (-) also called ground or 12v (-)) is on the other. so if you have a (-) ground trigger from the pcm (logical assumption), to make the electromagnet close and activate the high current connection between 87 and 30, all you need to do is put the opposite of the trigger on the opposite low current pin (12v (+)). wordy brain hurty, how about

if (-) trigger from pcm, put on 85 and use 12v (+) on the other pin 86.

it will also work if you put the (-) trigger on 86, and 12v (+) on 85, no difference whatsoever.

relays can also be used as diodes to isolate signals. so like I said wire two relays identically, with ac switch on 85, binary switch on 86, you can use a common 12v (+) high current wire on both 87s, but the output 30 of one to the ac clutch and the other output 30 to 87a of the fan relay. and then who cares how the fan is currently wired, using 87a just forces the fan on when the ac is turned on. if the temp switch ALSO turns on, the fan is already on, and if you turn the AC off with the temp trigger active (coolant above 180) the fan will stay on. easy peasy


tell me if you still need help I swear I can make a diagram.

[FAKKY]

Hey joedoh - thx for keeping with me.

I pretty much get your explanation - in theory if I was wiring two new relays (I forgot that PCM wire is ground)... although I'd have to draw it out and go over it 4-5 times ......

What Im not sure is if the FAN #1 and Fan#2 relays in the BP harness are effectively in parallel or whatever. eg Already wired like this. (pic atatched)

I think I would need to remove front and back covers to try and work out how they are tied together or not.

As I will be using #1 FAN for main radiator fan (temperature control) .........

[joedoh]

sorry, i missed that. reading back, fan 1 is for low speed? and fan 2 is for high speed? you can only use that on fans that have a separate low speed and high speed wire (three wires total). if your fan has two wires (power and ground), you can use either fan 1 or fan 2 output from pcm and the fan will run full speed. if you have a fan with 3 wires and two speeds, you will need two relays, which it sounds like you have in the harness? the 12v supply should be in parallel

older BMWs had big giant fan resistors on a 2 wire fan, so that a fan 1 signal went through the resistor, and fan 2 signal bypassed it, making a 2 wire fan a 2 speed fan, but the resistors predictably went bad all the time from the super high current being resisted, 12v at 30 watts us 3600 watts, cutting down the speed took about a 1/4 of that, so the resistor was in the area of 900watts! the resistors on the shelf at radio shack are 1/4 and 1/2 watt, so a fan resistor was huge and packed in sand to dissipate the heat of resistance (thats where the energy goes, 900w turned into heat and 2700 watts goes on to the fan)

[FAKKY]

Originally Posted by joedoh

sorry, i missed that. reading back, fan 1 is for low speed? and fan 2 is for high speed? you can only use that on fans that have a separate low speed and high speed wire (three wires total). if your fan has two wires (power and ground), you can use either fan 1 or fan 2 output from pcm and the fan will run full speed. if you have a fan with 3 wires and two speeds, you will need two relays, which it sounds like you have in the harness? the 12v supply should be in parallel

older BMWs had big giant fan resistors on a 2 wire fan, so that a fan 1 signal went through the resistor, and fan 2 signal bypassed it, making a 2 wire fan a 2 speed fan, but the resistors predictably went bad all the time from the super high current being resisted, 12v at 30 watts us 3600 watts, cutting down the speed took about a 1/4 of that, so the resistor was in the area of 900watts! the resistors on the shelf at radio shack are 1/4 and 1/2 watt, so a fan resistor was huge and packed in sand to dissipate the heat of resistance (thats where the energy goes, 900w turned into heat and 2700 watts goes on to the fan)

Hey Joe.
Yeah I have only a single speed main FAN for radiator/cooling and a single speed condensor fan. Didnt really need to but this DIY fuse block.

The BP fuse block relay DIY has two relays and just says FAN#1 and FAN#2 - doesnt have details about how those relays are configured. So my plan (originally) was to try and do the following

* AC on a dedicated circuit outside of PCM. Single standalone relay
* FAN#1 would be PCM controlled and tied to my single speed main radiator fan.

If I tried to use two relays for the AC/condensor fan (to split like you mentioned ) ... I'd like to use FAN#2 relay .... as otherwise its just sitting there unused. But hard to know how they set it up without tearing it all apart which I will probably do.

All they say is
"Two Fan Relays, an A/C Compressor Relay, and an Ignition Relay"

https://www.bp-automotive.com/produc...i-24x-engines/

<update>

I jumped on the webiste chat room and the guy said ...

"They are parallel. They are not in series."

So I guess that means I could use it ........ except ground would only activate when fan temp reached whatever point I set in PCM ?

[joedoh]

Originally Posted by FAKKY

Hey Joe.
Yeah I have only a single speed main FAN for radiator/cooling and a single speed condensor fan. Didnt really need to but this DIY fuse block.

The BP fuse block relay DIY has two relays and just says FAN#1 and FAN#2 - doesnt have details about how those relays are configured. So my plan (originally) was to try and do the following

* AC on a dedicated circuit outside of PCM. Single standalone relay
* FAN#1 would be PCM controlled and tied to my single speed main radiator fan.

If I tried to use two relays for the AC/condensor fan (to split like you mentioned ) ... I'd like to use FAN#2 relay .... as otherwise its just sitting there unused. But hard to know how they set it up without tearing it all apart which I will probably do.

All they say is
"Two Fan Relays, an A/C Compressor Relay, and an Ignition Relay"

https://www.bp-automotive.com/produc...i-24x-engines/

<update>

I jumped on the webiste chat room and the guy said ...

"They are parallel. They are not in series."

So I guess that means I could use it ........ except ground would only activate when fan temp reached whatever point I set in PCM ?

your explanations are finally getting through to me haha.

i will say people think fans need to come on more than they should, on my last e fan I used a set point of 200 degrees, because my thermostat was 190 and a set point below that would have just cycled the fan and thermostat mercilessly. so i wouldnt really worry about a higher set point myself.

[FAKKY]

Well .... Im not great at explaining things I do understand ..... so not surprised I'm confusing you and whoever else is reading.

So if this is just a regular relay (#fan2 -- just grounded by PCM control) - how would I integrate that into the AC circuit.

I drew a diagram based on what you mentioned before. Not sure if its right.

[joedoh]

i was thinking something like this





using two relays isolates the clutch and fan operation, and using 87a from the existing fan relay allows the fan to work in isolation from each discrete "on" signal.

dont make fun of my pink paper, its 1am and my daughter was making christmas cards with construction paper haha.

[FAKKY]

Thanks JoeDoh --- I will try and get my ahead around it .......
the only funny/good part is ........ me and a guy at work who works on home automation stuff were talking about it ...... and we were like --- I dont think you can do it with 2 relays ... needs 3.

So at least we got that far. Lol.

In the binary switch (-) part --- you mean ground one wire to chassis....... and split the other wire to both relays ?

[joedoh]

Originally Posted by FAKKY

Thanks JoeDoh --- I will try and get my ahead around it .......
the only funny/good part is ........ me and a guy at work who works on home automation stuff were talking about it ...... and we were like --- I dont think you can do it with 2 relays ... needs 3.

So at least we got that far. Lol.

In the binary switch (-) part --- you mean ground one wire to chassis....... and split the other wire to both relays ?

yep, ground one wire, other to both relays.

[FAKKY]

joeDoh --- thats awesome .... looks so much simplier when someone else does it/writes it down I stepped into each one thinkin...

truck at idle - both off
AC only on (not yet 180)
AC and FAN on

Seems perfect.


The 1st relay ---- you have written high current 12v+ for both pins 87 and 85 (coil side). Obviously both from battery - but one could be a low amp wire still (pin 85/coil) and pin 87 just have the higher amp fused wire right ?

You Da Man - even with your pink paper

[joedoh]

Originally Posted by FAKKY

but one could be a low amp wire still (pin 85/coil) and pin 87 just have the higher amp fused wire right ?

yep! most fans will have ignition there so the fan shuts off with the key. I didnt know how they wired the fan relay in your harness so really thats just extra information. if you have a fan relay in the harness you shouldnt need to worry about anything but the output wire and it goes to 87a on your efan relay.

Originally Posted by FAKKY

You Da Man - even with your pink paper

haha. I used to have 4 different pink dress shirts for work, probably more than any other color. my wife always commented about it.

[FAKKY]

Originally Posted by joedoh

yep! most fans will have ignition there so the fan shuts off with the key. I didnt know how they wired the fan relay in your harness so really thats just extra information. if you have a fan relay in the harness you shouldnt need to worry about anything but the output wire and it goes to 87a on your efan relay.




haha. I used to have 4 different pink dress shirts for work, probably more than any other color. my wife always commented about it.

thx man.

Heres where I got with ignition wiring and NSS. Followed a post eric had ... and some chat a while back.

[FAKKY]

Well I "ginny" rigged it one more time but through the proper circuits (relay etc) as eric had said. works like a champ.
Started first time in 'P'. Nothing in 'D' or 'R' etc.



Time to pull it all apart and loom it up and clean it up ...... get fenders on .... and finish a few things then get started on gauges and exhaust.